Under the leadership of new CEO Satya Nadella, Microsoft (MSFT) is trying to turn itself around after a few years of spotty earnings growth. Windows 8 was badly received, but Microsoft this week gave reviewers a preview of Windows 10, which the company hopes to release next spring. It’s skipping No. 9. The operating system returns to features that desktop users found useful but were abandoned in a move to be a more tablet-like interface.